<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width,initial-scale=1.0,minimum-scale=1.0,maximum-scale=1.0,user-scalable=no">
    <title>travel</title>
  </head>
  <body>
    <div id="app"></div>
    <!-- built files will be auto injected -->
  </body>
</html>
<script>
let htmlWidth=document.documentElement.clientWidth || document.body.clientWidth;
console.log(htmlWidth)
let htmlDom=document.getElementsByTagName('html')[0];
htmlDom.style.fontSize=htmlWidth/10+'px';
</script>
